JPH06163763A - Electronic-component mounted device and heat-dissipating slug used for it - Google Patents

Abstract

PURPOSE:To provide a heat-dissipating slug wherein it can be manufactured simply by using a low-cost material, its close contact strength with an electronic- component mounted device and it can enhance the durability of the electronic- component mounted device. CONSTITUTION:A heat-dissipating slug 10 is integrated with one part of an electronic-component mounting board 20, it is provided with an electronic- component mounting face, it is provided with a heat-dissipating face exposed from a sealing resin 40 in order to discharge heat from an electronic component 30 to the outside, and it is composed mainly of copper. A plated layer 11 composed of a metal whose ionization tendency is smaller than that of copper or of nickel is formed at least on the heat-dissipating face, and a blackening treatment is executed at least to its side face.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting board in which a radiation slug exposed from a sealing resin for radiating heat of an electronic component is integrated with the substrate, and an electronic component mounted on the substrate. The present invention relates to an electronic component mounting device obtained by molding a resin with a sealing resin, and a heat dissipation slag used for the device.

[0002]

2. Description of the Related Art There are various types of electronic component mounting apparatus in which electronic components are mounted on a so-called electronic component mounting substrate, and among them, the electronic component mounting substrate as shown in FIGS. An electronic component mounting apparatus having a structure in which a lead frame is integrated has been receiving attention. This electronic component mounting apparatus mounts the electronic component on the electronic component mounting substrate, and then seals the entire electronic component mounting substrate and the electronic component in a state where a part of the lead, which is the external connection means, is exposed. It is formed by molding.

In such an electronic component mounting apparatus,
The important issue is how to efficiently dissipate the heat from the electronic components that are embedded inside the encapsulating resin to the outside of the encapsulating resin, which has poor thermal conductivity. . One means of easily solving this problem is to use a heat dissipation slug as shown in FIG.
This heat dissipation slug is formed by using a good heat conductor such as metal, and a part of the heat dissipation slug is brought as close as possible to the electronic component in the sealing resin, preferably in close contact, and the other part is sealed with the sealing resin. By exposing it to the outside, the heat from the electronic component is effectively dissipated to the outside.

However, although the heat dissipation slag that satisfactorily dissipates such heat, it is formed of a material having good heat conductivity, that is, copper, which is easily oxidized and has poor adhesion to the sealing resin. Is common and includes the following problems. Since it is cheap, easy to process, and has a good heat conductor, it is most advantageous to use copper as a material for the heat dissipation slag. Chemical changes such as oxidation are likely to occur due to pretreatment with a solution of alkali, alkali or the like, which causes various adverse effects on electronic components and the like. If the heat-dissipating slag is made of a metal such as pure copper, the adhesiveness to the sealing resin is poor and there is a large difference in the coefficient of thermal expansion, so a peeling phenomenon easily occurs at the interface with the sealing resin. This allows the entry of moisture or the like, which has a harmful effect on electronic components, through the gap formed by the above. In order to improve the adhesion with the sealing resin, it is also possible to increase the contact area with the sealing resin by forming irregularities on this heat dissipation slug, but it is difficult to process it. Has become.

Therefore, as in the electronic component mounting apparatus shown in FIG. 4, the heat radiation surface of the heat radiation slag is soldered together with the leads to prevent corrosion of the heat radiation slag.
This conventional electronic component mounting device has a drawback in that the heat radiation slug and the lead cannot be subjected to good solder plating unless the heat radiation slug and the lead are electrically connected. Therefore, in the electronic component mounting apparatus shown in FIG. 4, at least the above can be solved, but it is not desirable to make the heat radiation slug and the lead in contact with each other.
It cannot be applied to the electronic component mounting device as shown in FIG.

Therefore, the inventors of the present invention have conducted earnest research on how to solve the above-mentioned problems (1) to (4) regardless of the type of electronic component mounting device. As a result, the present invention has been completed.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and the problem to be solved is to improve the adhesion strength of the heat dissipation slag to the electronic component mounting substrate and the sealing resin. It is to improve the durability of the electronic component mounting device.

It is an object of the invention according to claim 1 to provide an electronic component mounting apparatus having excellent electrical reliability and durability with a simple structure.

Further, the object of the invention according to claim 2 is that it can be easily manufactured with an inexpensive material, and when it is used as an electronic component mounting apparatus, the adhesion strength to the device is high and the electronic component mounting is performed. It is to provide a heat dissipation slag that can improve the durability of the device.

[0010]

Means for Solving the Problems To solve the above problems, the means adopted by the invention according to claim 1 will be described with reference to the reference numerals used in the embodiments. The main component is copper having a heat radiation surface exposed from the stop resin 40, at least a heat radiation surface on which a plating layer 11 made of a metal or nickel having a smaller ionization tendency than copper is formed, and at least the side surface of which is blackened. The heat dissipation slug 10 is integrated by closing the opening 24 formed in the electronic component mounting board 20, and the whole of the electronic component mounting board 20 and the electronic component 30 mounted thereon is dissipated. The sealing resin 40 with the heat radiation surface of the slag 10 exposed
The electronic component mounting apparatus 100 "is characterized in that the electronic component mounting apparatus 100" is configured by performing the molding by.

Further, the means adopted by the invention according to claim 2 is likewise "integrated with a part of the electronic component mounting substrate 20 and having an electronic component mounting surface.
A heat dissipation slag 10 having copper as a main component and having a heat dissipation surface exposed from the sealing resin 40 in order to release the heat from 0 to the outside.
The heat dissipation slag 10 "is characterized in that a plating layer 11 made of metal or nickel having a smaller ionization tendency than copper is formed on at least the heat dissipation surface, and at least the side surface thereof is subjected to blackening treatment.

[0012]

Next, the operation of the heat radiation slug 10 and the electronic component mounting apparatus 100 according to the present invention will be described. First, in the heat radiation slug 10, this has a polygonal plate shape or a disk shape having two parallel main surfaces. Since it is in the form of a plate, etc., it can be formed by a simple process such as punching, and its manufacture is very easy. That is, in this type of heat dissipation slag, various complicated shapes have been proposed for the purpose of increasing the contact area of the electronic component mounting substrate and the sealing resin of the electronic component mounting apparatus. In the heat radiation slag 10, since the blackened surface 12 described later enhances the adhesion strength to the electronic component mounting substrate 20 and the sealing resin 40,
Even if it has a simple shape as shown in FIG. 1,
That is, it functions as a heat dissipation member.

Particularly, since the heat dissipation slug 10 has a rectangular parallelepiped shape, the opening 24 on the electronic component mounting substrate 20 side to which the heat dissipation slug 10 is to be fixed is also formed, for example, by rotating a rotating drill at a right angle to its axis. It can also be easily performed by counter boring, which is carried out by moving in the direction of cutting to perform cutting.

In the heat dissipation slag 10,
Since the plating layer 11 is formed on the heat dissipation surface exposed from the sealing resin 40 when the electronic component mounting apparatus 100 is formed,
Even if the heat dissipation slag 10 is made of a copper material, it does not easily corrode. To put it the other way around, this heat dissipation slag 10 has a plating layer 11 on its heat dissipation surface.
Since the heat-dissipating slag 10 is positively formed, the heat-dissipating slag 10 can be made of a copper material having good workability, high heat conductivity, and relatively inexpensive and easily available.
In addition to being flat, it is easy to manufacture.

In the electronic component mounting apparatus 100 configured by using the heat dissipation slug 10 as described above, as shown in FIGS. 2 and 3, the side surface of the heat dissipation slug 10 that directly contacts the sealing resin 40 is illustrated. Since it is the blackened surface 12, this blackened surface 12 exerts a so-called "anchor effect" with respect to the sealing resin 40, and the heat dissipation slug 10 is firmly bonded to the sealing resin 40. . Therefore, the peeling phenomenon does not occur at the interface between the two.

Therefore, in this electronic component mounting apparatus 100, infiltration of moisture from the interface between the heat radiation slug 10 and the sealing resin 40 is not permitted, and the electronic component mounting apparatus 100 has excellent durability. Since each lead 22 projects from the sealing resin 40, its interface is also exposed on the side surface of the electronic component mounting apparatus 100. However, even in the portion of the lead 22 that contacts the sealing resin 40. It suffices if blackening is applied.

As a matter of course, in the electronic component mounting apparatus 100, the heat slug 1 is disposed on the upper surface of FIGS. 2 and 3.
Although the plated layer 11 of 0 is exposed, it goes without saying that the plated layer 11 prevents oxidation of the heat dissipation slag 10 itself. In particular, the electronic component mounting apparatus 100
As a result, after completion, it is necessary to perform solder plating on each lead 22 protruding from the sealing resin 40 to improve electrical connection to a conductor circuit on another substrate. This electronic component mounting device 1 in liquid
In some cases, the plating layer 11 formed of a metal having a smaller ionization tendency than copper or nickel may surely protect the heat radiation slag 10. Further, at the interface between the sealing resin 40 and the heat radiation slag 10, since the two are firmly adhered to each other as described above, the pretreatment liquid does not enter the electronic component mounting apparatus 100 from this interface. Is as described above.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a heat slug 10 according to each claim and an electronic component mounting apparatus 100 constituted by using the same will be described with reference to the embodiments shown in the drawings. The electronic component mounting apparatus according to claim 1 100 is the heat dissipation slag 1 according to claim 2.
Since it is constructed by using 0, the embodiments of the invention according to both claims will be described by focusing on the electronic component mounting apparatus 100.

First, the heat dissipation slug 10 must be formed. The heat dissipation slug 10 is formed to a thickness of 1.5 m.
A plating layer 11 made of a metal having a smaller ionization tendency than copper or nickel is formed on the entire surface of the copper plate of m to be the heat radiation surface. In this case, it is preferable to use aluminum, nickel, nickel / gold, platinum, or silver as the plating layer 11, and as shown in FIG. 1A, the plating layer 11 is provided only on one surface of the copper material. When it is desired to form, it is sufficient to perform it on both surfaces exposed by overlapping two copper plates. Then, the copper plate on which the plating layer 11 is formed is cut or punched to obtain individual pieces having a substantially rectangular parallelepiped shape as shown in FIG. 1, and the individual pieces are subjected to blackening treatment. As a result, at least the side surface is made the blackened surface 12. Since the plating layer 11 is a metal having an ionization tendency smaller than that of nickel or copper, even if the individualized heat slag 10 is removed into the blackening treatment tank, only the exposed portion of the copper is blackened. Therefore, it is very convenient.

The heat slug 10 thus formed has
There are two types as shown in (a) or (b) of FIG. In the heat dissipation slug 10 shown in FIG. 1A, the lower surface side in the drawing is the heat dissipation surface, and the plating layer 11 is formed only in this portion. Twelve. The heat radiation slag 10 shown in FIG.
Since it is 2, it is suitable to be integrated with the opening 24 of the electronic component mounting substrate 20 via the adhesive layer 23 as shown in FIG. In addition, since the heat dissipation slug 10 shown in FIG. 1B has the plating layers 11 formed on the upper and lower surfaces in the figure, the plating layer 11 on the inner surface side is mounted for the electronic component 30 as shown in FIG. The electronic component mounting apparatus 1 is suitable for a part
00 is easy to manufacture.

FIG. 2 shows an electronic component mounting apparatus 100 constructed by using the heat dissipation slag 10 shown in FIG. 1 (a). Electronic component mounting for constructing the electronic component mounting apparatus 100 is shown. The substrate 20 for a lead is connected to the conductor circuit 21 formed on the front surface side of the lead 2 which serves as an external connection means.
2 are directly connected to each other, and an opening 24 that serves as a housing for the electronic component 30 and the heat radiation slug 10 is formed in the substantially central portion thereof. Then, in the electronic component mounting substrate 20, the adhesive layer 2 is formed in the opening 24.
Each lead 22 is electrically independent from the heat radiation slag 10 which is housed and fixed via the lead wire 3.

For this electronic component mounting substrate 20,
After mounting the electronic component 30 on the mounting portion of the heat dissipation slug 10, the electronic component 30 and the conductor circuit 21 on the electronic component mounting substrate 20 are electrically connected by the bonding wire 31. 20 and electronic component 3
The entire 0 is molded with the sealing resin 40 in a state where the outer end of each lead 22 and the plated layer 11 that becomes the heat dissipation surface of the heat dissipation slug 10 are exposed. This allows
The plating layer 11 of the heat dissipation slag 10 and the outer ends of the leads 22 are the electronic component mounting apparatus 100 exposed from the sealing resin 40.

FIG. 3 shows an electronic component mounting apparatus 100 constructed by using the heat dissipation slug 10 shown in FIG. 1B. The electronic component mounting substrate 20 of this electronic component mounting apparatus 100 is shown. Insulating base material is integrated on both surfaces of the lead 22. Further, in this electronic component mounting apparatus 100, the electronic component 30 is directly mounted on the plating layer 11 which is inside the heat dissipation slug 10,
As a result, the ground or power supply terminal of the electronic component 30 is connected to the heat dissipation slug 10. Since the other configurations are similar to those of the electronic component mounting apparatus 100 shown in FIG. 2, the description thereof will be omitted by giving the same reference numerals to those in FIG.

[0024]

As described above in detail, in the invention according to claim 1, "the electronic component mounting surface and the heat radiation surface exposed from the sealing resin 40 are provided, and at least the heat radiation surface has a smaller ionization tendency than copper. Forming a plated layer 11 made of a metal or nickel, and closing the opening 24 formed on the electronic component mounting substrate 20 with the heat dissipation slag 10 whose main component is blackened at least on its side surface. The electronic component mounting substrate 20 and the electronic component 30 mounted on the electronic component mounting substrate 20 are sealed and integrated, and are molded by the sealing resin 40 in a state where the heat radiation surface of the heat radiation slag 10 is exposed. It has its characteristic, and by this,
It is possible to provide an electronic component mounting device having excellent electrical reliability and durability with a simple structure.

Further, in the invention according to claim 2,
“The electronic component mounting board 20 is integrated with a part thereof and has an electronic component mounting surface, and has a heat radiating surface exposed from the sealing resin 40 to radiate heat from the electronic component 30 to the outside. It is a heat dissipation slag 10 containing copper as a main component, and a plating layer 11 made of a metal or nickel having a smaller ionization tendency than copper is formed on at least the heat dissipation surface, and at least the side surface thereof is subjected to blackening treatment. " It has the feature that it can be easily manufactured with an inexpensive material, has a high adhesion strength to the electronic component mounting device, and also improves the durability of the electronic component mounting device. It is possible to provide a heat dissipation slag.

[Brief description of drawings]

FIG. 1 is a perspective view of a heat dissipation slug according to the present invention.

FIG. 2 is a sectional view of an electronic component mounting apparatus configured using the heat dissipation slug shown in FIG.

FIG. 3 is a cross-sectional view of an electronic component mounting device configured using the heat dissipation slug shown in FIG. 1B.

FIG. 4 is a sectional view of a conventional electronic component mounting apparatus.

[Explanation of symbols]

 10 Heat Dissipation Slug 11 Plating Layer 12 Blackened Surface 20 Electronic Component Mounting Substrate 21 Conductor Circuit 22 Lead 23 Adhesive Layer 24 Opening 30 Electronic Component 40 Sealing Resin 100 Electronic Component Mounting Device

Claims (2)

[Claims] 1. A plating layer, which has an electronic component mounting surface and a heat radiation surface exposed from a sealing resin, is formed on at least the heat radiation surface and is made of a metal or nickel whose ionization tendency is smaller than that of copper, and at least a side surface thereof is black. The heat-dissipating slag containing copper as a main component, which has been subjected to the chemical treatment, is integrated by closing the opening formed in the electronic component mounting board, and the entire electronic component mounting board and the electronic components mounted on it. An electronic component mounting apparatus, characterized in that the above-mentioned heat-dissipating surface of the heat-dissipating slag is exposed by molding with a sealing resin. 2. An electronic component mounting surface which is integrated with a part of an electronic component mounting substrate and which has a heat radiating surface exposed from a sealing resin for radiating heat from the electronic component to the outside. The heat-dissipating slag containing copper as a main component, characterized in that a plating layer made of a metal or nickel having a smaller ionization tendency than copper is formed on at least the heat-dissipating surface, and at least the side surface thereof is subjected to blackening treatment. Heat dissipation slag to do.